save project

my_tree.py

@@ -9,7 +9,17 @@ w.bgcolor('wheat')      # wheat小麦
 # 移动到起点
 # 移动到起点
 pen.left(90)
 pen.left(90)
 pen.up()
 pen.up()
-pen.backward(150)    # 后退
 pen.down()
 pen.down()
-
+def tree(n):
+    if n >= 50: 
+        pen.forward(n)
+        pen.right(30)
+        tree(n-50)
+        pen.left(60)
+        tree(n-50)
+        pen.right(30)
+        pen.up()
+        pen.backward(n)
+        pen.down()
+tree(100)
 turtle.done()
 turtle.done()